Drink more green! Biodynamics and holistic farming methods aren't just dancing with fairies! Enjoy the different flavours and yes, even health benefits, of wines from nature friendly vineyards. There are various factors which distinguish a wine as being "organic" (or 'Bio' as they are often called in Europe):
Organic wines must be made from organically grown grapes, free of pesticides, from a Certified Organic vineyard. So in order to have organically grown grapes, the vineyard manager must implement a variety of different practices to maintain the vines.
Of course, the absence of harmful chemicals like synthetic herbicides and fungicides from the production of organic wine is better for the health of everyone involved, including those who drink it!
In the making of most wines, sulphur dioxide (SO2) is added during the process to prevent oxidation and other faults. Some of it combines with sugars, but the remaining 'free' sulphur dioxide is effective as a preservative. Organic wines produced in the USA virtually prohibit the use of added sulphur - they must contain less than 100 ppm sulphites.